Automatic supplementary source for electric stop-motions



Jan, 13, 1953 A. CRAWFORD 2,625,027

AUTOMATIC SUPPLEMENTARY SOURCE FOR ELECTRIC STOE-MOTIONS Filed Feb. 28,1949 4 Sheets-Sheet l o 4- 0 III J /Z 4 22 I 5 5 26% M 6 2 Q 6/ 0 1 I e[Z 75 4 I 5 a I 5 Z5 M" Alredfiag Jan, 13, 1953 A. CRAWFORD 2,625,027

AUTOMATIC SUPPLEMENTARY SOURCE FOR ELECTRIC STOP-MOTIONS Filed Feb. 28,1949 F795 55 5' HI 4 Sheets-Sheet 2 4 m WW, {I 42 4 A mz E? A WF W WJan. 13, 1953 A. CRAWFORD 2,625,027

AUTOMATIC SUPPLEMENTARY SOURCE FOR ELECTRIC STOP-MOTIONS Filed Feb. 28,1949 A 4 Sheets-Sheet s Hg. i7

35"; M F i' mmm:

Jan. 13, 1953' A. CRAWFORD 2,625,027

AUTOMATIC SUPPLEMENTARY SOURCE FOR ELECTRIC STOP-MOTIONS Filed Feb. 28,1949 4 Sheets-Sheet 4 F I 1 a2 g a5, 4 a

T I I! IJ I' 64 75 Patented Jan. 13, 1953 UNITED STATES PATENT OFFICEAUTOMATIC SUPPLEMENTARY SOURCE FUR ELECTRIC STOP-MOTIONS of New JerseyApplication February 28, 1949, Serial No. 78,825

9 Claims.

This invention relates to stop motions of the general class disclosed inUnited States Letters Patent No. 2,145,754, and more particularly toimprovements in stop motions of the type wherein an electricallycontrolled knockoff device is associated with a control circuit in suchmanner that the knockoff device is released by energization of the saidcontrol circuit and, when set, will remain in set condition as long asthe said circuit is deenergized.

In stop motions of this class the normally open control or detectorcircuit is conventionally connected to a source of electrical energy,such for example as a lighting circuit, which is independent of thesource from which power is applied to the knitting machine and, sincethe operation of the stop motion is dependent upon the closing of thesaid circuit, any interruption of the energy supply from the source suchas that resulting for example from a blown fuse or from inadvertentdisconnection of the detector circuit from the source will have noimmediate effect upon the stop motion or upon the operation'of themachine. If after such interruption the control circuit is closed byactuation of one of the detector devices associated therewith, the stopmotion will fail to function with obviou undesirable results.

A primary object of the present invention is to provide means operativeautomatically upon failure of the primary source of electrical energyfor immediately connecting a supplementary energy source in the detectorcircuit.

Another object of the invention is to provide means whereby, under theabove-outlined emergency circumstances, the stop motion will stillfunction instantaneously and automatically to stop the knitting machine.

To this latter and the invention contemplates the provision in theelectrical control system of a separate source of energy together withmeans normally energized from the primary source to maintain thesecondary source disconnected from the knockoff device, said means beingoperative upon failure of the primary source toconnect the secondarysource with the knockoff device in a manner to actuate the latter and tothereby interrupt the operation of the machine.

The invention will be more readily understood by reference to theattached drawings, wherein:

Fig. l is a fragmentary elevational view of a knockoff device made inaccordance with the invention, and of the immediately associated partsof the knitting machine;

,. Fig. 2 is a diagrammatic view in perspective 2 showing a portion ofthe knitting machine and the lements of the knockoff device;

Fig. 3 is an enlarged vertical sectional view of the knockoff device;

Fig. 4 is a sectional view on the line 4-4, Fig. 3;

Fig. 5 is a sectional view on the line 55, Fig. 4;

Fig. 6 is a fragmentary elevational view showing details of the latchdevice;

Fig. 7 is a front view of the secondary power source unit forming anelement of the invention;

Fig. 8 is a sectional view on line 88, Fig. 7;

Fig. 9 is a sectional view on line 9-9, Fig. '7;

Fig. 10 is a diagrammatic view showing the electrical system, and

Fig. 11 is a wiring diagram illustrating a modification within the scopeof the invention.

The invention will be more readily understood by reference first toFigs. 1 and 2 of the drawings. Therein the reference numeral l indicatesa fra mentary part of the main bedplate of a knitting machine ofconventional type, such for example as that disclosed in the aforesaidUnited States Patent No. 2,145,754. The reference numeral 2 indicates acasing within which are housed elements of the knockoff deviceillustrated in detail in subsequent figures of the drawings, said casingbeing supported on a bracket 3 attached to the said main frame. 4 is atrip shaft which extends through the casing 2 and which is connectedthrough a lever 5 attached to its lower end and through a link 6 with aknockoff shaft 1, the latter shaft having attached thereto a lever B,and the said link 6 being pivotally connected to that lever and to thelever 5 on the shaft 4.

The knockoff shaft 1 which is journaled in a bearing 9 on the main frameI carries two arms or levers II and I2' respectively. The lever llengages one end of a screw IS in a lever is attached to one end of arock shaft l5 which is supported in a journal 16 on a bracket 1?, andthe other end of the lever carries a catch [8 arranged to engage, and tonormally support against the pull of a spring 20, a brake lever 19 on abrake shaft 2i. This shaft carries an eccentric 22 which i embraced by astrap 23 and the strap carries a reach rod in the form of a screw 24which engages one arm of 'a brake element 25 operatively associated withthe main shaft (not shown) of the machine.

The knockoff lever I2 is arranged for operative engagement with a clutchshift-rod-retaining lever 26 which is pivotally mounted on the mainframe of the machine and which normally interlocks with thespring-actuated shifting rod of a. clutchassociated with a drive pulleyloose on the aforementioned main shaft of the knitting machine andcontrolling the connection of the pulley with the shaft. In the drawingsthe shift rod and clutch are not shown.

The functions of the brake and clutch will be understood by thosefamiliar with the art and the general mode of operation of the portionof the knockoff mechanism described above is clearly set forth in UnitedStates Patent No. 2,145,754 aforesaid. Normally the trip shaft 4 ismaintained by devices hereinafter described in a position wherein thebrake is retracted and the clutch is engaged to connect the drive pulleywith the shaft. When the knockoff is tripped and the shaft 4 therebyreleased the clutch is disengaged and the brake applied to bring thknitting machine to an immediate halt.

Referring more particularly to Figs. 3 to 6 of the drawings, it will benoted that the shaft 4 has a collar 3| attached to that portion thereofwhich occupies the interior of the casing 2, and a spring 32 embracesthe shaft and has one end thereof anchored in the collar 3| and theother end anchored in a sleeve or bushing 33 secured in the wall of thecasing. Projecting transversely from the collar 3| is a pin 34 whichprojects through an aperture 35 in a wall 36 of the casing.

Normally the spring 32 will hold the shaft 4 in a position wherein thecollar 3| and the pin 34 occupy the positions shown in broken lines inFig. 5, it being noted that the said collar is extended radially at oneside to form a shoe 3'! which, in the said normal position of the shaft4, bears against a stop 38 on the said wall 36. Pivotally attached at 39to the wall 36 is a lever 4| having a semi-circular recess 42 Which,under conditions hereinafter described, is adapted to receive the pin 34so that the lever may act as a latch to retain the pin and therefore theshaft 4 in the position shown in full lines in Fig. 5 against thetendency of the spring 32 to shift the shaft and pin to the dotted linepositions as previously described. Pivotally attached to the outer endof the lever 4| is one link 43 of a toggle, the other link of which isindicated by the reference numeral 44.' This latter link, WhichisU-shaped in form as best shown in Fig. 3, is pivotally supported upon'apin 45 which projects from the wall 36 and is pivotally connected at 46to the link 43. When the lever 4| is in the retracted position as shownin Fig. 6, the link 44 will seat against a stop pin 41 on the wall 36.In this position the toggle 43-44 is broken. When the shaft 4 is rockedto carry the pin 34 from the position of Fig. 6 to the position shown infull lines in Fig. 5, in which position the pin will overlie the recess42 of the lever 4|, this lever will be elevated by engagement of the pinwith the upper edge portion 46 thereof, thereby extending the toggle43-44 to the position indicated in Fig. 4 and bringing the pin 34 intothe recess 42. The lever 4|, as long as it is supported in the elevatedposition, will act to retain the pin and the shaft 4 in the retractedposition against the pressure of the spring 32.

The toggle 4344 is adapted to be retained in the extended position by abell crank lever 48 which is pivotally supported on a pin 49 projectingfrom the wall 36. One arm 5| of the lever 48 extends transversely intoengagement with the upper extremity of the link 44, as best shown inFig. 4, and when thus engaged with the said link tends to hold thetoggle 43+ in the extended position against the pressure of the spring32 which, acting through the shaft 4 and pin 34, tends to force thelever 4| downwardly, such movement of the lever 4| being possible onlywhen the said toggle is broken. As shown in Fig. 4 the thrust of thelink 44 upon the arm 5| of the bell crank lever 48 is in the directionof the pivot 49 and a coiled spring 52 carried by the pivot pin 49exerts pressure upon the lever 48 to hold this lever in the operativeposition with respect to the link 44, as shown in Fig. 4. The other arm53 of the lever 48 has a flange 54 which is arranged in operativerelation to the armature 55 of an electromagnet 56 supported on abracket 51 on the wall 36. Normally, and as hereinafter more fully setforth, the magnet 56 is deenergized, but when energized this magnet willexert sufficient force to draw the flange 54 toward the armature 55against the resisting pressure of the spring 52 so that the arm 5| ofthe lever 48 will be elevated clear of the extremity of the link 45,thereby releasing the toggle 4344 and permitting the lever 4| to movedownwardly and to release the pin 34. Upon release of the toggle asdescribed above, and subsequent deenergization of the magnet 56 theparts will assume the relative positions as shown in Fig. 6. The devicemay be reset to the latched position by means of a reset lever 58 at theupper end of the shaft 4. I

With reference now to the diagram of Fig. 10, it will be noted that theelectromagnet 56 of the knockoff device described above is connected ina control circuit which receives its energy through a transformer 6|,the primary coil 62 of which is connected with a suitable source ofelectrical energy such for example as an available lighting circuit. Thesecondary coil 63 of the transformer is in series with the electromagnet56 in a circuit which includes a collector ring 64, a brush 66 and oneor more normally open detector switches of which one is indicated at 61.In operation the collector ring 64 rotates with the cam ring of theknitting machine and the brush 66 continuously contacts the ring 64. Thecircuit also includes a switch 68, one terminal of which is grounded asalso is one terminal of the detector switch 67. The detector switch 61is normally open and thus the aforedescribed grounded circuit isnormally broken. In accordance with the present invention the electricalcontrol system also includes a shunt circuit which contains the coil 69of a magnetic switch 1| which is associated with a grounded circuitdesignated generally by the reference numeral 12. The coil 69 of theswitch H is normally energized and when energized retains the switch 7|in open position as shown in Fig. 10, thereby breaking the circuit 12.This circuit 12 also contains a suitable source of electrical energy 13,in the form for example of dry cells, and also a switch 14, one terminalof which is grounded. In the present instance the switch 14 ismechanically connected with the switch 68 so that these two switchesopen and close simultaneously.

With the arrangement described above, any failure of the connectionbetween the primary of the transformer 6| and the source of energy withwhich it is connected will result in a deenergization of the coil 69 andconsequent closing of the switch 1| and circuit 12. The source of energy13 will then energize the electromagnet 56 and will thereby trip theknockoff device described above. Simultaneously and as hereinafterdescribedthe switches 68 and 14 will be opened. Under normalconditionsenergy will be sup pliedthrough the transformer secondary 53to the control circuit so that if the detector switch 61 is closed theelectromagnet 56 will be energi'zed in obvious manner tothereby actuatethe knockoff device. The circuit 12 with the supplementary source ofenergy 13 will function as described above to trip the knockoff devicein the event of failure of the transformer circuit, and will therebyavoid possible damage to the machine which. might result in event ofinadvertent failure of the transformer circuit and subsequent faultyoperation of the knitting machine which, while closing the detectorswitch 61, would then fail to interrupt the operation of the machine.

With reference to Figs. 1 and 2'- it will be noted that the transformer6t is secured in the present instance to the side of the casing 2 of theknockoii device, and the electrically actuated switch 1| and thesupplementary source of electrical energy 13 are contained in thepresent instance in a casing 15 which is mounted in the present instanceon a bracket 16 attached to the main frame I of the knitting machine.

With reference to Figs. 4, and 6, it will be noted that the switch 68 ofthe circuit described above comprises a contact element 11 which engagesthe pin 34 only when that pin occupies the recess 42 of the lever 4| andwhich, when the pin 34 is released from this recess, is free fromcontact with any grounded portion of the machine. The switch 14 (seeFig. 5) consists of a contact element 18 which engages the shoe 31 alsoonly when the pin 34 occupies the recess 42 and which is left free fromcontact with any grounded portion of the machine when the pin 34 hasbeen released and the shaft 4 rotated under pressure of the spring 32.It will be apparent therefore that when the knockoff device is trippedthe switches 68 and 14 will be automatically opened thereby to break thecircuit of the supplementary source of energy 13.

In the operation of the device described above the control circuit willoperate normally as long as the transformer 6| is connected to theprimary source of energy. If for any reason the primary coil 62 of thetransformer is deenergized the supplementary source of energy 13 will beimmediately thrown into the circuit containing the electromagnet 56 andwill trip the knockoff device independently of the detector switch 61 tothereby bring the machine to a halt.

In the modified device shown in Fig. 11, I have provided for automaticsubstitution of the supplementary energy source in the detector circuitupon failure of the primary source, but in this instance withoutaccompanying actuation of the knockoii device. In Fig. 11 the essentialelements of the apparatus have been identified by the same referencenumerals used in Fig. 10. In this case, however, the electricallycontrolled switch 69-1! of the embodiment shown in Fig. has beenreplaced by a double-pole doublethrow relay designated generally by thereference numeral 8 I. When this relay is energized, which occurs duringthe periods when the transformer 61 is energized from the primarysource, the switch arm 82 of the relay BI is elevated into engagementwith the contacts 83, 83 whereby the detector circuit is conditioned foroperation upon closing of the switch 61. When the primary source ofenergy fails with the resultant deenergization of the transformer 61 theswitch arm 82 of the relay is permitted to drop into engagement with thecontact elements 84. 84 thereby connecting the supplementary energysource 13in the detector circuit and maintaining that circuit incondition for actuation of the electromagnet 56 of the knockolf' devicewhen the switch 61 is closed.

In this case, therefor, the substitution of the supplementary source 13for the primary source of energy does-not have the effect ofautomatically actuating the knockoff device of the stop motion sothatthe machine will remain in operation until actuation of the detectorswitch 61 closes the knockoff device.

In order that the operator may be aware of the fact that the primarysource has failed and that the supplementary source has beenautomatically connected in the detector circuit a visible or audiblesignal may be associated with the supplementary'source in such mannerthat" when this source is connected in the circuit the signal will beactuated. In the present instance the signal device is shown in the formof a lamp 85 placed in series with the supplementary source 13. It willbe apparent that when the operator has reestablished the connection ofthe detector circuit with the primary energy source that the relay 8|will operate automatically to restore the circuit by way of the contacts83, 83 and will break the connection of the circuit with thesupplementary source 13.

I claim:

1. An electric stop motion comprising in combination a knockoff device,an electric actuator for said device, a primary source of electricalenergy for connection with said actuator, a normally open detectorswitch for controlling the connection of said actuator with said source,a secondary source of electrical energy normally disconnected from theactuator, and means for automatically connecting the secondary sourcewith the actuator independently of the said detector switchupon failureof the primary source.

2. A stop motion according to claim 1 including a switch controlling theconnection of the secondary source to the actuator, said switch havingelectrical actuating means connected to the primary source.

3. A stop motion according to claim 2 wherein the said switch whichcontrols the connection of the secondary source to the actuator isnormally maintained in the open position by the said electricalactuating means connected to the primary source and closes automaticallywhen the supply of energy fro-m the primary source fails.

4. A stop motion according to claim 1 wherein means is provided forautomatically disconnecting the secondary source from the actuatorsubsequent to the connection of the actuator with the secondary source.

5. In an electric stop motion, a knockoff device, an electric actuatorfor said device, a normally open detector switch, a primary source ofelectric energy, an electrical system including said actuator, switch,and primary source, and providing for energization of the actuator fromsaid source when the switch is closed, said system including also anindependent secondary source of electric energy and a normally openswitch for segregating said secondary source from the said actuator, andmeans responsive to failure of the primary source for closing the lastnamed switch so as to provide for delivery of energy to the actuatorfrom the secondary source.

6. An electric stop motion according to claim 5 wherein the saidelectrical system includes parallel portions containing the said sourcesrespectively.

'7. An electric stop motion according to claim 6 wherein the detectorswitch is in series with the said parallel portions in the system.

8. An electric stop motion according to claim 7 wherein an electricsignal element is included in the parallel portion which contains thesaid secondary source, 7

9. In an electric stop motion, a knockofi' device, an electric actuatorfor said device, a normally open detector switch, a primary source ofelectric energy, an electrical system including said actuator, switch,and primary source, and providing for energization of the actuator fromsaid source when the switch is closed, said system including also anindependent secondary source of electric energy and a normally openswitch for segregating said secondary source from the said actuator,means j responsive to failure of the primary source for closing the lastnamed switch so as to provide for delivery of energy to the actuatorfrom the secondary source, said electrical system having parallelportions respectively containing the said sources of electric energy andthe said detector switch being positioned in that parallel portion ofthe said system which contains the said primary source of energy.

' ALFRED CRAWFORD.

REFERENCES CITED The following references are of record in the file of.this patent:

